Apparatuses/devices for launching and recovery of daughter boats from and onto a mother vessel/ship are already known.
Such mother boats may be lifeboats or rigid inflatable boats (commonly termed RIBs) and other designs of boats or vessels, often deployed by the navy or by maritime rescue operators.
For launching daughter boats from a mother vessel, davits are connected to a line at each end of the boat and the boat is hoisted into water. This is time consuming and leaves the chances of detachment of the boats wide open. Similar chances exist during recovery of the mother boat as well. Hence, this traditional method and similar such methods have potentialities of causing loss of life and material.
Deployment of ramp to avoid the problem in the aforesaid paragraph is known but then chances of collision exist in such ramp technology, which is nonetheless dangerous.
Slightly more advanced technology for launching and recovery of daughter boats are also known. Davit assemblies on each side of the mother vessel are known, which are placed above a stationary cradle. Several transversely movable cradles carry these boats below the davit assemblies on the stationary cradle along rails for launching. However, the existence of too many transversely movable cradles limit the total space available for handling the daughter boats on the deck of the mother vessel. Further, too many davit assemblies have to be deployed for picking up the boats from the transversely moving cradles and for launching and retrieving the boats.
Japanese patent publication JP2002087376, discloses a simplified construction of a davit type boat-lifting device comprising a pair of hydraulically drivable columnar cradles turnably connected to a mother ship. A pair of wire ropes are delivered from the turnable ends of the cradle. The cradles are turned and a mounted boat lifted via wire ropes is lifted into and out of the mother ship. WO 20122069853, discloses a cradle for launching and recovering a boat. The cradle is shaped to have an axis and to support a boat. A moving mechanism moves the cradle in a first stowed position and to a second ramp position.
U.S. Pat. No. 1,118,499 A describes an apparatus for launching lifeboats from ships, comprising a series of frames pivotally mounted on the side of the ship, where each frame having a horizontal boat supporting member, said members being arranged out of horizontal alinement, and rollers carried by said horizontal members.
U.S. Pat. No. 2,319,855 A describes a motor torpedo boat carrier having upper and lower decks, a compartment between the decks for stowing motor torpedo boats, a hatch in the upper deck communicating with said compartment, a movable cradle in said compartment for supporting a motor torpedo boat, vertical guide rails in said compartment adjacent and supported by said hatch, upstanding arms on said cradle adapted to interlock with said guide rails for guiding the vertical movement of the cradle, a travelling carriage on the upper deck for carrying said cradle across the upper deck, depending guide rails carried by said carriage adapted to align with the guide rails in said compartment for co-acting with the arms on said cradle.
U.S. Pat No. 1,361,236 B describes a device for launching lifeboats from a ship, where the lifeboats are stored in a room in the aft part of the ship, from which room to a location close to the ship's water line a glide path in the form of a downward inclined tunnel to convey the lifeboats, is provided.
The prior art documents acknowledged in the preceding paragraph and similar such documents not only have a complicated construction, but also fail to teach a simple mechanism by means of which a large number of daughter boats can be handled on and from the mother vessel, using a fewer number of davits. Further, prior art technology does not specifically teach how a single davit can handle a substantially large number of daughter boats.
The present invention solves the drawbacks of prior art as recited in the preceding paragraph and meets other associated needs by applying a very simple apparatus having a plurality of longitudinally movable cradles which can securely hold, receive, lift and lower daughter boats and can simultaneously interact with a single transversely movable cradle. A single davit can pick up or deliver on the transversely movable cradle, a large number of daughter boats one after another.